Factors that influence stroke in Dahl salt-sensitive rats.

Japanese rat chow and cerebral sympathetic denervation increase the incidence of stroke in stroke-prone spontaneously hypertensive rats. The purpose of this study was to determine if Japanese rat chow and sympathetic denervation would result in a high incidence of stroke in Dahl salt-sensitive (DS) rats, which have not been reported to be stroke prone. At 3 to 4 weeks of age, DS rats of both sexes began consumption of a high salt Japanese or American chow and underwent unilateral superior cervical sympathetic ganglionectomy. The rats fed American chow were found to have a high incidence of stroke (46%). Rats fed Japanese chow had shorter survival and a higher incidence of stroke (78%) than rats fed American chow (p less than 0.05). Blood pressure increased faster in DS rats fed Japanese chow (p less than 0.05). Metabolic studies indicated that increased sodium consumption accounted for only part of the acceleration of hypertension by Japanese rat chow. In DS rats grouped for equal levels of blood pressure, those fed Japanese chow had modestly reduced survival (p less than 0.05) compared with those fed American chow and had a greater incidence of stroke (85% vs 38%; p less than 0.05). Location of stroke was not influenced by removal of sympathetic nerves.(ABSTRACT TRUNCATED AT 250 WORDS)